This invention relates to chewing gums having longer lasting sweetness and flavor intensity.
Commercially available chewing gums generally comprise a water-soluble bulk portion and a water-insoluble gum base portion. Incorporated within the gum base portion may be elastomers, fillers and softeners to improve the texture of the gum. The gum may also contain flavors and sweetening agents such as sugar or, for sugarless chewing gums, artificial sweetening agents such as saccharin, acesulfame, and aspartame.
However, one of the limitations of commercially available chewing gums is their rapid loss of both sweetness and flavor intensity during chewing. One solution, disclosed in U.S. Pat. Nos. 3,943,258, 3,982,023 and 4,036,992 is to add aspartame to the gum composition in addition to the sweetener already present (which could also be aspartame). Where only aspartame is used to sweeten the gum, it is stated that the amount of aspartame required is greater than 0.3% by weight of the final composition. Where other sweeteners are used, including non-dipeptide artificial sweeteners, aspartame is used at a concentration as low as about 0.1% by weight of the final gum composition. The result is a gum whose normal sweetness and flavor is extended.
In addition, one of the limitations of sugarless gums is their bitter aftertaste when a sweetening agent like acesulfame is used at a concentration level to produce a gum having a normally accepted sweetness intensity. To remedy the bitter aftertaste, U.S. Pat. No. 4,536,396 discloses the use of Alitame in minor amounts to mask the bitter aftertaste of acesulfame and produce a synergistic sweetening effect. The amount of Alitame used in the examples is 0.01% or less by weight of the total gum composition.
Alitame, L-.alpha.-Aspartyl-N-(2,2,4,4-tetramethyl-3-thietanyl)-D-alaninamide hydrate, is a sweetening agent described in U.S. Pat. No. 4,411,925. This patent shows the use of Alitame with a sweetening agent like sorbitol or corn syrup in an amount to sweeten edible products, including chewing gum. The patent also discloses that Alitame is approximately 2000 times sweeter than sucrose, advantageously making it sweeter than aspartame, which is only up to 200 times sweeter than sucrose. Therefore, it is estimated that Alitame is about 10 times sweeter than aspartame. From tests using Alitame in gum it is estimated that the amount of Alitame needed to impart normally accepted sweetness to sugarless chewing gum is from about 0.01% to about 0.03% by weight of the final chewing gum composition.
Furthermore, it has been found that other properties of Alitame make its use in gum more advantageous than aspartame. Aspartame has a low solubility in water or solvent. On the other hand, Alitame is much more soluble in water and solvents such as alcohols. Therefore, it can be more easily formulated and used in manufacturing chewing gum.